On a default Gnome installation, pressing the Print Screen takes a screenshot. I often press this button by accident, so I prefer to disable this behavior. …

Gnome's "Taking Screenshots" documentation states that this (and any Gnome) keybinding can be changed or disabled using the Keyboard Shortcuts preference tool: Open System – Preferences – Keyboard Shortcuts – Desktop, then highlight "Take a screenshot" and press backspace to disable that keybinding.

This didn't work for me on one installation of Gnome 2.30.0/Mandriva 2010.2. One solution would be to throw the baby out with the bathwater and uninstall gnome-utils, but I didn't want to lose bonobo, which is also included in that package. Instead I made gnome-screenshot non-executable (as root, chmod a-x /usr/bin/gnome-screenshot). If I anticipated frequent updates to that package, I would also place that command in cron.daily.